I asked for evidence of this and you responded with a generic statement attempting to educate me on vacuum electronics. You did not in fact provide any evidence.bishopdante wrote: The fact is that you can now put pcbs and IC packages inside the glass assembly,
I know how electronics work in a vacuum. I studied and worked in UHV science for a number of years. I know what a photomultiplier is. Those also have leads for external control and generally do not include any pcbs and ICs inside the vacuum glass enclosure.bishopdante wrote: Wed May 04, 2022 12:36 am In the fast majority of cases, semiconductors replaced vacuum / radio-emission devices, rather than supplementing them - but not in all industries. Photomultiplier tubes as a notable example have remained very popular, particularly for spectrometry. Contemporary semiconductor techniques offer magnificent levels of potential miniaturisation: https://arxiv.org/pdf/2203.09929.pdf
PCB technology fares OK with vacuum, and the constraints and processes are well-known in the space industry: https://resources.altium.com/p/how-to-p ... um-systems
In the case of the photomultiplier tubes pictured earlier - and also most of the various items to be found in particle accelerators - you will see that the enclosures are very much using all the tools in the box, and freely combine all available types of electronics packaging technology within a vacuum device.
Lots of the later CRT design was pretty snazzy, also, but certainly in the vast majority of cases for ease of maintenance and assembly, and because of different factory processes and locations, the PCB is outside the glass and connected via a ribbon cable, rather than inside it.
My point about nesting NuTubes to stop them ringing like a bell was largely humorous, but also acoustic - vacuum is a different environment with properties that can be useful in lots of ways including acoustic. Interference and resonance of all sorts is a whole heap of potential complexity which we could harness a bunch of different ways in the design of a complex device.
The military aerospace industry did quite a lot of nested babushka doll vacuum devices, with big metal cans protecting assemblies including small glass vacuum tubes.
Additionally with the advent of robotics, a vacuum manufacturing environment is now possible, along with all manner of precision-bonding and micro-welding / soldering processes now being possible. Additionally there were no laser cutters, and no computers to control them, and a 1930s tube factory is basically almost entirely mechanical.
With regards to CRTs, I am also well aware of the possible complexity of CRTs, having repurposed many for use as focused electron emission devices for plasmonic excitation. I have also travelled to and worked with a company to design a custom CRT for the purpose of operating in the 30kV range. I actually arced one of the exposed leads to my cold-lab-erect-booby when applying too high a voltage to an adjacent lead while hunched over the vacuum chamber, hovering too close to the external connectors. Those do not include pcbs or ICs in the enclosure either.
To be clear, I am not arguing that electronics can not go in vacuums. I have done it many times. I am asking for evidence to support your wild and seemingly made up claims that "The fact is that you can now put pcbs and IC packages inside the glass assembly."
Jon